Simultaneous Spectrophotometric Multicomponent Determination of Folic Acid, Thiamine, Riboflavin, and Pyridoxal by Using Double Divisor–Ratio Spectra Derivative–Zero Crossing Method

Abstract

A graphical method based on the double divisor–ratio spectra derivative–zero crossing was proposed for the spectrophotometric multicomponent analysis of synthetic mixtures containing folic acid (vitamin B₀), thiamine (vitamin B₁), riboflavin (vitamin B₂), and pyridoxal (vitamin B₆) in the presence of strongly overlapping signals without any chemical separation. The graphical method is based on the use of derivative signals of the ratio spectra by using double divisor. The selected data of ultraviolet‐visible absorption spectra consisted of points corresponding to the spectral region 225–475 nm. The linear determination ranges were 1–26 µg mL⁻¹ of B₀, 4–50 of µg mL⁻¹ of B₁, 1–28 µg mL⁻¹ of B₂, 6–42 µg mL⁻¹ of B₆ in a buffer solution at (pH 5.8). The proposed method applied to the simultaneous determination of four vitamins by using synthetic quaternary mixtures. The obtained results were statistically compared with each other.

Keywords:

• Folic acid
• Thiamine
• Riboflavin
• Pyridoxal
• Double divisor–ratio spectra derivative–zero crossing